1,2-dichloroethylene [CAS 540-59-0] is a material that has recently found increased utility for a variety of uses. 1,2-dichloroethylene can be named 1,2-dichloroethene and is also referred to as symmetrical dichloroethylene. 1,2-dichloroethylene exists as a mixture of two geometric isomers; namely, the trans isomer [CAS 156-60-5] and the cis isomer [CAS 156-59-2]. The isomers can be used separately or together in various proportions. It is reported that 1,2-dichloroethylene can be used as a low temperature extraction solvent for organic materials, such as dyes, perfumes, lacquers and thermoplastics, as a solvent for the manufacture of rubber solutions, as a coolant in refrigeration plants, and as a chemical intermediate in the synthesis of other chlorinated hydrocarbon solvents.
1,2-dichloroethylene can be produced by the direct chlorination of acetylene at temperatures of from approximately 40° C. to 80° C., or by the reduction of 1,1,2,2-tetrachloroethane. It is also formed as a by-product during the production of other C2 chlorinated hydrocarbons, e.g., trichloroethylene. Recently, market requirements for 1,2-dichloroethylene have increased. Because of this increased demand, it would be desirable to find a means to produce increased amounts of 1,2-dichloroethylene without incurring the corresponding substantial capital investment required to build new manufacturing facilities for that purpose.